New donor!

[guf]

i hope i"m not wasting my money but i figured i had to get this one. up here in my small rural county of Humboldt in Northern cali. There is never any of our trucks so when there is i figure i HAVE to get them --i found both my trucks on craigslist. MY second was a 70 step side with supposedly a new 350/th350 with only 1000 miles on it. but it sat for 9 years. The truck is very rusty --but came with some not so rusty doors, fenders, and a hood in the bed and actually there was a cab but i decided not to take it do to lack of space. So now i have a 71 with a 350/3 speed manual and a 70 with the new 350/Th350. I'm think of putting the engine and transmission in my 71 but am unsure of the quality of them. they are obviously way newer than the rest of the truck and it does drive and shift smooth. Then cleaning up the new body panels and put them on my 71. should i test fit everything before spending the time to clean them up. and the 350/th350 ? do a compressions test to see if its worth changing over? can i pull the engine and tranny out as one piece and just place it in my new 71. then switch the steering column and radiator. any suggestions?<center>